The authors describe the construction of a comprehensive set of high-resolution grids of monthly climate at spatial resolutions of 10 minutes for Europe and 0.5 degrees for the global land surface. Five climate variables are included: temperature, diurnal temperature range, precipitation, vapour pressure, and cloud cover. The set comprises the observed climate record (1901-2000), a control scenario (1901-2100) and 16 scenarios of projected future climate (2001-2100). The 16 climate change scenarios represent all combinations of four emissions scenarios and four global climate models (GCMs), covering 93% of the range of uncertainty in global warming in the 21st century published by the Intergovernmental Panel on Climate Change. Thus these scenarios permit users to assess the implications for climate impacts of some of the major sources of uncertainty in future climate. The scenarios were constructed by combining time-series of global warming and patterns of change from GCMs with the baseline climate and sub-centennial variability from the observed record. Thus these grids provide homogenous 200-year transient scenarios (1901-2100) for users projecting the future impacts of climate change using environmental models. These grids are publicly available through the Climatic Research Unit ((http://www.cru.uea.ac.uk).